Electromagnetic radiation (EMR) is a form of energy emitted and absorbed by charged particles which exhibit wave-like behavior as it travels through space. EMR is classified according to the frequency of its wave. It consists of radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays. The electro-magnetic radiation is called radio-frequency (RF) radiation when it is within the radio wave range.
RF interference is disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source within the radio wave range. The disturbance may interrupt, obstruct, or otherwise degrade or limit the effective performance of the circuit. These effects can range from a simple degradation of data to a total loss of data. The source may be any object, artificial or natural, that carries rapidly changing electrical currents, such as an electrical circuit, the Sun or the Northern Lights.
Hospital is an environment highly dense with apparatus emitting RF radiation, ranging from medical equipment, through communication devices such as intercoms and call units to electric personal gear of hospital staff, patients and their families. All these electric apparatus may interfere and disturb the function of each other.
The most important outcome of RF interference within a hospital is dysfunction of medical equipment. For example, an MRI that depends on an RF coil which its shift resulting from RF interference will change the readings of the machine and as a result will give inaccurate data. The RF interference will also obstruct RF-dependent cordless interaction between medical devices. For example, a monitor transmitting data to the nurse unit may send inaccurate and shifted signals that may cost a life. Although not life threatening, RF interference of medical devices with cellular reception is a burdensome nuisance, especially for patient and their relatives as well as the medical staff.
There thus remains a long felt and unmet need for a uniform non-fringing magnetic field resonance MRI device that functions within an active RF-magnetic environment without being affected by other ferromagnetic RF transmitting devices and without affecting their function.